A newly discovered asteroid designated 2018 NX flew past Earth at a distance of 0.30 LD / 0.00078 AU (116 686 km / 72 505 miles) on July 7, 2018, one day before it was discovered.
Asteroid 2018 NX belongs to the Aten group of asteroids. It was discovered at Palomar Mountain, ZTF at 09:39 UTC on July 8, about 15 hours after it made its closest approach to Earth somewhere above the Central Pacific Ocean.
Its estimated diameter is between 7.7 and 17 meters (25 – 55 feet) and it flew past us at a speed of 4.15 km/s (relative to the Earth) at 18:12 UTC on July 7.
This is the 37th known asteroid to flyby Earth within 1 lunar distance since the start of the year. Just a few hours later, another newly discovered asteroid flew past us at a distance of 0.32 LD.
2018 NX won’t come as close as this at least until 2118.